ランキング (合計) - Ceek.jp Altmetrics

1 0 0 0 OA 第二次世界大戦期における原爆の物理学的研究と核兵器工学の成立

著者: 山崎正勝
出版者: 日本科学史学会
雑誌: 科学史研究 (ISSN:21887535)
巻号頁・発行日: vol.25, no.160, pp.225-234, 1986 (Released:2021-09-22)

The first idea of atomic bomb proposed by E. Fermi and, especially, L. Szilard, who was the real writer of Einstein's letter to President F D Roosevelt in 1939, was shown to be based on a fast neutron chain reaction in normal uranium which was later proved to be inert for fast neutrons At that time such an idea was also proposed independently by L. Peierls in Britain, but he soon abandoned it because of its great critical mass estimated theoretically by himself. The large scale enrichment of uranium was at first pursuited to produce a thermal nuclear chain reaction (the nuclear reactor) effectively. This stream was thus independent of that for the construction of the bomb at the early stage Those two streams above were, however, joined together in 1940 by O. Frisch and Peierls in their memorandum on a super bomb, which first showed the technological principle of atomic bomb based on the fast neutron chain reaction in pure uranium 235 In contrast to these two streams in the U.S. were kept divisitive by compartmentalization of information adopted by V.Bush, the chairman of NDRC. The idea of the Frisch-Peierls memorandum is studied in detail in comparison with the MAUD reports, the British official reports, completed in the summer of 1941. It is shown that the influence of the British research on the atomic bomb was the most important factor for the full start of the development of the bomb in the U.S. in the autumn of 1941. The problem on independence between NAS report of November 6,1941 and the MAUD reports is discussed.

2022-09-25 05:10:00
1 はてなブックマーク

1 0 0 0 OA 動力技術の発達法則についての石谷説の再検討

著者: 門脇重道
出版者: 日本科学史学会
雑誌: 科学史研究 (ISSN:21887535)
巻号頁・発行日: vol.25, no.160, pp.255, 1986 (Released:2021-09-22)

2022-09-25 05:10:00
1 はてなブックマーク

1 0 0 0 OA 明治中期の少年雑誌における科学ジャーナリストの役割 ―中川重麗の場合―

著者: 東徹
出版者: 日本科学史学会
雑誌: 科学史研究 (ISSN:21887535)
巻号頁・発行日: vol.25, no.160, pp.245-254, 1986 (Released:2021-09-22)

The juvenile magazine Shonen'en was the first to put in articles on science and technology in Japan. As it was well received, many magazines just like Shonen'en were published one after another. Shigeaki Nakagawa was one of famous journalists who wrote the articles on science in these juvenile magazines. He learned German from R. Lehmann who was a teacher of Ogakusha in Kyoto. He learned physical sciences through the learning of German When he was a teacher of Kyoto Normal School, he wrote many science textbooks on referring to F Schoedler's Das Buch der Natur. Then he resigned his post as a teacher, and he was engaged on a staff of the education magazine He published a magazine Shonen'en with Teisaburo Yamagata in 1888. Articles which he wrote in juvenile magazines incorporated a variety of ideas designed to arouse interest in science and technology. His articles had a great influence on the popularization of science to the youth. Enlightenment of science to the youth became gradually performed by specialists of science The main medium of science to the youth changed from the juvenile magazine to the book. So he ceased to play the role of popularizer of science to the youth.